Americans face a growing threat to their health. And it could have a negative impact in Canada.

The U.S. House of Representatives recently voted to pass the American Health Care Act (AHCA). If the bill becomes law, it could leave millions in the U.S. without care.

The confusion around health care in America is palpable. Just over a month ago, efforts to pass AHCA imploded before the bill could even be brought to a vote. Now there’s a real chance it could come to fruition, transforming American health care for the second time in a decade.

Danielle Martin

Why is the issue of health care in the U.S. so fraught? And is Canada immune to the social whiplash underway south of us?

As physicians observing from both sides of the border, we see two key reasons this issue continues to polarize opinion in the U.S. But it’s ultimately trade policy, not health policy, that will put Canadian medicare in the crosshairs.

First, unlike Canadians, Americans have not yet come to view health care as an expression of core national values, deserving of protection as a fundamental right of citizenship. In Canada, there’s no serious doubt about whether the country should continue to have universal health coverage. The debate is mostly centred around how to expand public financing to broaden coverage (for example, to include universal prescription medicines and home care), and how to improve systems of delivery to make care better and reduce wait times.

Sandro Galea

This is because offering universal coverage is central to the Canadian identity. For Canadians, health care arose from a national determination to take care of each other during times of need.

But the U.S. is still wrestling with what it means to offer health care to citizens and where that fits in the country’s values system.

Second, the U.S. lacks a structural component that has been at the core of Canadian health care for decades: the federal requirement to provide insurance for all necessary doctor and hospital services, sustained through a single payer that guarantees coverage. In the U.S., there has been no such federal legislative push, and little talk of bringing health care under the umbrella of a single, accountable and democratically-supported vision.

The existing U.S. health-care law, the Affordable Care Act (ACA), is a patchwork of legislative compromises and deals struck between interest groups, administered by many stakeholders. While the legislative architecture of Canadian health care has unified the system under the Canada Health Act and buffered it from multiple challenges, the more ad hoc nature of the ACA leaves it vulnerable to the type of existential threat it now faces from the Republican Congress.

Until Americans decide that health care is a right that should be supported by the federal government as an extension of national values, and resolve to create a legislative structure with teeth to support that vision, the health-care debate can’t be resolved because it’s not grounded in public consensus.

But Canadians should not feel smug.

Not only are internal challenges an ongoing threat to Canadian medicare, the ripples of President Donald Trump’s administration are soon to be felt north of the border and will test the resolve of Canadian governments.

What does Trump’s agenda mean for Canadian health care?

Other than driving doctors to activism that might even send them north across the border, threats to the Canadian system as a result of the Trump agenda relate less to the repeal of Obamacare and more to his intention to renegotiate the North American Free Trade Agreement (NAFTA).

Canadian health care has explicitly been protected under NAFTA, shielding the system from American industry that would otherwise bring not just American-style health care, but actual American health care across the border. If strong provisions that exclude health care from free trade aren’t maintained, and in fact strengthened, in any renegotiated trade deal, American insurance companies and health-care delivery organizations could claim the right to a Canadian private health-care market.

As private insurers stand poised to lose market share in the U.S. with the repeal-and-replace gambit, hunger for access to a new market is sure to grow.

Canadian governments and citizens need to remember that not far from here, health-care insurance is a good sold in the marketplace like softwood lumber.

If the health-care battle and the free-trade battle intersect at the Canada-U.S. border, Canadians may become more than interested observers of the Trump presidency.

Danielle Martin, MD, is vice-president Medical Affairs and Health System Solutions at Women’s College Hospital in Toronto and an expert with EvidenceNetwork.ca. Her book, Better Now: Six big ideas to improve health care for all Canadians, was published in January. Sandro Galea, MD, DrPH, is the Robert A Knox professor and dean of the Boston University School of Public Health. His book, Healthier: Fifty thoughts on the foundations of population health, will be published in June.